drivers/tee/tee_core.c

   1 /*
   2  * Copyright (c) 2015-2016, Linaro Limited
   3  *
   4  * This software is licensed under the terms of the GNU General Public
   5  * License version 2, as published by the Free Software Foundation, and
   6  * may be copied, distributed, and modified under those terms.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  */
  14
  15 #define pr_fmt(fmt) "%s: " fmt, __func__
  16
  17 #include <linux/cdev.h>
  18 #include <linux/device.h>
  19 #include <linux/fs.h>
  20 #include <linux/idr.h>
  21 #include <linux/module.h>
  22 #include <linux/slab.h>
  23 #include <linux/tee_drv.h>
  24 #include <linux/uaccess.h>
  25 #include "tee_private.h"
  26
  27 #define TEE_NUM_DEVICES 32
  28
  29 #define TEE_IOCTL_PARAM_SIZE(x) (sizeof(struct tee_param) * (x))
  30
  31 /*
  32  * Unprivileged devices in the lower half range and privileged devices in
  33  * the upper half range.
  34  */
  35 static DECLARE_BITMAP(dev_mask, TEE_NUM_DEVICES);
  36 static DEFINE_SPINLOCK(driver_lock);
  37
  38 static struct class *tee_class;
  39 static dev_t tee_devt;
  40
  41 static int tee_open(struct inode *inode, struct file *filp)
  42 {
  43         int rc;
  44         struct tee_device *teedev;
  45         struct tee_context *ctx;
  46
  47         teedev = container_of(inode->i_cdev, struct tee_device, cdev);
  48         if (!tee_device_get(teedev))
  49                 return -EINVAL;
  50
  51         ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
  52         if (!ctx) {
  53                 rc = -ENOMEM;
  54                 goto err;
  55         }
  56
  57         kref_init(&ctx->refcount);
  58         ctx->teedev = teedev;
  59         INIT_LIST_HEAD(&ctx->list_shm);
  60         filp->private_data = ctx;
  61         rc = teedev->desc->ops->open(ctx);
  62         if (rc)
  63                 goto err;
  64
  65         return 0;
  66 err:
  67         kfree(ctx);
  68         tee_device_put(teedev);
  69         return rc;
  70 }
  71
  72 void teedev_ctx_get(struct tee_context *ctx)
  73 {
  74         if (ctx->releasing)
  75                 return;
  76
  77         kref_get(&ctx->refcount);
  78 }
  79
  80 static void teedev_ctx_release(struct kref *ref)
  81 {
  82         struct tee_context *ctx = container_of(ref, struct tee_context,
  83                                                refcount);
  84         ctx->releasing = true;
  85         ctx->teedev->desc->ops->release(ctx);
  86         kfree(ctx);
  87 }
  88
  89 void teedev_ctx_put(struct tee_context *ctx)
  90 {
  91         if (ctx->releasing)
  92                 return;
  93
  94         kref_put(&ctx->refcount, teedev_ctx_release);
  95 }
  96
  97 static void teedev_close_context(struct tee_context *ctx)
  98 {
  99         struct tee_device *teedev = ctx->teedev;
 100
 101         teedev_ctx_put(ctx);
 102         tee_device_put(teedev);
 103 }
 104
 105 static int tee_release(struct inode *inode, struct file *filp)
 106 {
 107         teedev_close_context(filp->private_data);
 108         return 0;
 109 }
 110
 111 static int tee_ioctl_version(struct tee_context *ctx,
 112                              struct tee_ioctl_version_data __user *uvers)
 113 {
 114         struct tee_ioctl_version_data vers;
 115
 116         ctx->teedev->desc->ops->get_version(ctx->teedev, &vers);
 117
 118         if (ctx->teedev->desc->flags & TEE_DESC_PRIVILEGED)
 119                 vers.gen_caps |= TEE_GEN_CAP_PRIVILEGED;
 120
 121         if (copy_to_user(uvers, &vers, sizeof(vers)))
 122                 return -EFAULT;
 123
 124         return 0;
 125 }
 126
 127 static int tee_ioctl_shm_alloc(struct tee_context *ctx,
 128                                struct tee_ioctl_shm_alloc_data __user *udata)
 129 {
 130         long ret;
 131         struct tee_ioctl_shm_alloc_data data;
 132         struct tee_shm *shm;
 133
 134         if (copy_from_user(&data, udata, sizeof(data)))
 135                 return -EFAULT;
 136
 137         /* Currently no input flags are supported */
 138         if (data.flags)
 139                 return -EINVAL;
 140
 141         shm = tee_shm_alloc(ctx, data.size, TEE_SHM_MAPPED | TEE_SHM_DMA_BUF);
 142         if (IS_ERR(shm))
 143                 return PTR_ERR(shm);
 144
 145         data.id = shm->id;
 146         data.flags = shm->flags;
 147         data.size = shm->size;
 148
 149         if (copy_to_user(udata, &data, sizeof(data)))
 150                 ret = -EFAULT;
 151         else
 152                 ret = tee_shm_get_fd(shm);
 153
 154         /*
 155          * When user space closes the file descriptor the shared memory
 156          * should be freed or if tee_shm_get_fd() failed then it will
 157          * be freed immediately.
 158          */
 159         tee_shm_put(shm);
 160         return ret;
 161 }
 162
 163 static int
 164 tee_ioctl_shm_register(struct tee_context *ctx,
 165                        struct tee_ioctl_shm_register_data __user *udata)
 166 {
 167         long ret;
 168         struct tee_ioctl_shm_register_data data;
 169         struct tee_shm *shm;
 170
 171         if (copy_from_user(&data, udata, sizeof(data)))
 172                 return -EFAULT;
 173
 174         /* Currently no input flags are supported */
 175         if (data.flags)
 176                 return -EINVAL;
 177
 178         shm = tee_shm_register(ctx, data.addr, data.length,
 179                                TEE_SHM_DMA_BUF | TEE_SHM_USER_MAPPED);
 180         if (IS_ERR(shm))
 181                 return PTR_ERR(shm);
 182
 183         data.id = shm->id;
 184         data.flags = shm->flags;
 185         data.length = shm->size;
 186
 187         if (copy_to_user(udata, &data, sizeof(data)))
 188                 ret = -EFAULT;
 189         else
 190                 ret = tee_shm_get_fd(shm);
 191         /*
 192          * When user space closes the file descriptor the shared memory
 193          * should be freed or if tee_shm_get_fd() failed then it will
 194          * be freed immediately.
 195          */
 196         tee_shm_put(shm);
 197         return ret;
 198 }
 199
 200 static int params_from_user(struct tee_context *ctx, struct tee_param *params,
 201                             size_t num_params,
 202                             struct tee_ioctl_param __user *uparams)
 203 {
 204         size_t n;
 205
 206         for (n = 0; n < num_params; n++) {
 207                 struct tee_shm *shm;
 208                 struct tee_ioctl_param ip;
 209
 210                 if (copy_from_user(&ip, uparams + n, sizeof(ip)))
 211                         return -EFAULT;
 212
 213                 /* All unused attribute bits has to be zero */
 214                 if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_MASK)
 215                         return -EINVAL;
 216
 217                 params[n].attr = ip.attr;
 218                 switch (ip.attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
 219                 case TEE_IOCTL_PARAM_ATTR_TYPE_NONE:
 220                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
 221                         break;
 222                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
 223                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
 224                         params[n].u.value.a = ip.a;
 225                         params[n].u.value.b = ip.b;
 226                         params[n].u.value.c = ip.c;
 227                         break;
 228                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
 229                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
 230                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
 231                         /*
 232                          * If we fail to get a pointer to a shared memory
 233                          * object (and increase the ref count) from an
 234                          * identifier we return an error. All pointers that
 235                          * has been added in params have an increased ref
 236                          * count. It's the callers responibility to do
 237                          * tee_shm_put() on all resolved pointers.
 238                          */
 239                         shm = tee_shm_get_from_id(ctx, ip.c);
 240                         if (IS_ERR(shm))
 241                                 return PTR_ERR(shm);
 242
 243                         /*
 244                          * Ensure offset + size does not overflow offset
 245                          * and does not overflow the size of the referred
 246                          * shared memory object.
 247                          */
 248                         if ((ip.a + ip.b) < ip.a ||
 249                             (ip.a + ip.b) > shm->size) {
 250                                 tee_shm_put(shm);
 251                                 return -EINVAL;
 252                         }
 253
 254                         params[n].u.memref.shm_offs = ip.a;
 255                         params[n].u.memref.size = ip.b;
 256                         params[n].u.memref.shm = shm;
 257                         break;
 258                 default:
 259                         /* Unknown attribute */
 260                         return -EINVAL;
 261                 }
 262         }
 263         return 0;
 264 }
 265
 266 static int params_to_user(struct tee_ioctl_param __user *uparams,
 267                           size_t num_params, struct tee_param *params)
 268 {
 269         size_t n;
 270
 271         for (n = 0; n < num_params; n++) {
 272                 struct tee_ioctl_param __user *up = uparams + n;
 273                 struct tee_param *p = params + n;
 274
 275                 switch (p->attr) {
 276                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
 277                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
 278                         if (put_user(p->u.value.a, &up->a) ||
 279                             put_user(p->u.value.b, &up->b) ||
 280                             put_user(p->u.value.c, &up->c))
 281                                 return -EFAULT;
 282                         break;
 283                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
 284                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
 285                         if (put_user((u64)p->u.memref.size, &up->b))
 286                                 return -EFAULT;
 287                 default:
 288                         break;
 289                 }
 290         }
 291         return 0;
 292 }
 293
 294 static int tee_ioctl_open_session(struct tee_context *ctx,
 295                                   struct tee_ioctl_buf_data __user *ubuf)
 296 {
 297         int rc;
 298         size_t n;
 299         struct tee_ioctl_buf_data buf;
 300         struct tee_ioctl_open_session_arg __user *uarg;
 301         struct tee_ioctl_open_session_arg arg;
 302         struct tee_ioctl_param __user *uparams = NULL;
 303         struct tee_param *params = NULL;
 304         bool have_session = false;
 305
 306         if (!ctx->teedev->desc->ops->open_session)
 307                 return -EINVAL;
 308
 309         if (copy_from_user(&buf, ubuf, sizeof(buf)))
 310                 return -EFAULT;
 311
 312         if (buf.buf_len > TEE_MAX_ARG_SIZE ||
 313             buf.buf_len < sizeof(struct tee_ioctl_open_session_arg))
 314                 return -EINVAL;
 315
 316         uarg = u64_to_user_ptr(buf.buf_ptr);
 317         if (copy_from_user(&arg, uarg, sizeof(arg)))
 318                 return -EFAULT;
 319
 320         if (sizeof(arg) + TEE_IOCTL_PARAM_SIZE(arg.num_params) != buf.buf_len)
 321                 return -EINVAL;
 322
 323         if (arg.num_params) {
 324                 params = kcalloc(arg.num_params, sizeof(struct tee_param),
 325                                  GFP_KERNEL);
 326                 if (!params)
 327                         return -ENOMEM;
 328                 uparams = uarg->params;
 329                 rc = params_from_user(ctx, params, arg.num_params, uparams);
 330                 if (rc)
 331                         goto out;
 332         }
 333
 334         rc = ctx->teedev->desc->ops->open_session(ctx, &arg, params);
 335         if (rc)
 336                 goto out;
 337         have_session = true;
 338
 339         if (put_user(arg.session, &uarg->session) ||
 340             put_user(arg.ret, &uarg->ret) ||
 341             put_user(arg.ret_origin, &uarg->ret_origin)) {
 342                 rc = -EFAULT;
 343                 goto out;
 344         }
 345         rc = params_to_user(uparams, arg.num_params, params);
 346 out:
 347         /*
 348          * If we've succeeded to open the session but failed to communicate
 349          * it back to user space, close the session again to avoid leakage.
 350          */
 351         if (rc && have_session && ctx->teedev->desc->ops->close_session)
 352                 ctx->teedev->desc->ops->close_session(ctx, arg.session);
 353
 354         if (params) {
 355                 /* Decrease ref count for all valid shared memory pointers */
 356                 for (n = 0; n < arg.num_params; n++)
 357                         if (tee_param_is_memref(params + n) &&
 358                             params[n].u.memref.shm)
 359                                 tee_shm_put(params[n].u.memref.shm);
 360                 kfree(params);
 361         }
 362
 363         return rc;
 364 }
 365
 366 static int tee_ioctl_invoke(struct tee_context *ctx,
 367                             struct tee_ioctl_buf_data __user *ubuf)
 368 {
 369         int rc;
 370         size_t n;
 371         struct tee_ioctl_buf_data buf;
 372         struct tee_ioctl_invoke_arg __user *uarg;
 373         struct tee_ioctl_invoke_arg arg;
 374         struct tee_ioctl_param __user *uparams = NULL;
 375         struct tee_param *params = NULL;
 376
 377         if (!ctx->teedev->desc->ops->invoke_func)
 378                 return -EINVAL;
 379
 380         if (copy_from_user(&buf, ubuf, sizeof(buf)))
 381                 return -EFAULT;
 382
 383         if (buf.buf_len > TEE_MAX_ARG_SIZE ||
 384             buf.buf_len < sizeof(struct tee_ioctl_invoke_arg))
 385                 return -EINVAL;
 386
 387         uarg = u64_to_user_ptr(buf.buf_ptr);
 388         if (copy_from_user(&arg, uarg, sizeof(arg)))
 389                 return -EFAULT;
 390
 391         if (sizeof(arg) + TEE_IOCTL_PARAM_SIZE(arg.num_params) != buf.buf_len)
 392                 return -EINVAL;
 393
 394         if (arg.num_params) {
 395                 params = kcalloc(arg.num_params, sizeof(struct tee_param),
 396                                  GFP_KERNEL);
 397                 if (!params)
 398                         return -ENOMEM;
 399                 uparams = uarg->params;
 400                 rc = params_from_user(ctx, params, arg.num_params, uparams);
 401                 if (rc)
 402                         goto out;
 403         }
 404
 405         rc = ctx->teedev->desc->ops->invoke_func(ctx, &arg, params);
 406         if (rc)
 407                 goto out;
 408
 409         if (put_user(arg.ret, &uarg->ret) ||
 410             put_user(arg.ret_origin, &uarg->ret_origin)) {
 411                 rc = -EFAULT;
 412                 goto out;
 413         }
 414         rc = params_to_user(uparams, arg.num_params, params);
 415 out:
 416         if (params) {
 417                 /* Decrease ref count for all valid shared memory pointers */
 418                 for (n = 0; n < arg.num_params; n++)
 419                         if (tee_param_is_memref(params + n) &&
 420                             params[n].u.memref.shm)
 421                                 tee_shm_put(params[n].u.memref.shm);
 422                 kfree(params);
 423         }
 424         return rc;
 425 }
 426
 427 static int tee_ioctl_cancel(struct tee_context *ctx,
 428                             struct tee_ioctl_cancel_arg __user *uarg)
 429 {
 430         struct tee_ioctl_cancel_arg arg;
 431
 432         if (!ctx->teedev->desc->ops->cancel_req)
 433                 return -EINVAL;
 434
 435         if (copy_from_user(&arg, uarg, sizeof(arg)))
 436                 return -EFAULT;
 437
 438         return ctx->teedev->desc->ops->cancel_req(ctx, arg.cancel_id,
 439                                                   arg.session);
 440 }
 441
 442 static int
 443 tee_ioctl_close_session(struct tee_context *ctx,
 444                         struct tee_ioctl_close_session_arg __user *uarg)
 445 {
 446         struct tee_ioctl_close_session_arg arg;
 447
 448         if (!ctx->teedev->desc->ops->close_session)
 449                 return -EINVAL;
 450
 451         if (copy_from_user(&arg, uarg, sizeof(arg)))
 452                 return -EFAULT;
 453
 454         return ctx->teedev->desc->ops->close_session(ctx, arg.session);
 455 }
 456
 457 static int params_to_supp(struct tee_context *ctx,
 458                           struct tee_ioctl_param __user *uparams,
 459                           size_t num_params, struct tee_param *params)
 460 {
 461         size_t n;
 462
 463         for (n = 0; n < num_params; n++) {
 464                 struct tee_ioctl_param ip;
 465                 struct tee_param *p = params + n;
 466
 467                 ip.attr = p->attr;
 468                 switch (p->attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
 469                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
 470                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
 471                         ip.a = p->u.value.a;
 472                         ip.b = p->u.value.b;
 473                         ip.c = p->u.value.c;
 474                         break;
 475                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
 476                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
 477                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
 478                         ip.b = p->u.memref.size;
 479                         if (!p->u.memref.shm) {
 480                                 ip.a = 0;
 481                                 ip.c = (u64)-1; /* invalid shm id */
 482                                 break;
 483                         }
 484                         ip.a = p->u.memref.shm_offs;
 485                         ip.c = p->u.memref.shm->id;
 486                         break;
 487                 default:
 488                         ip.a = 0;
 489                         ip.b = 0;
 490                         ip.c = 0;
 491                         break;
 492                 }
 493
 494                 if (copy_to_user(uparams + n, &ip, sizeof(ip)))
 495                         return -EFAULT;
 496         }
 497
 498         return 0;
 499 }
 500
 501 static int tee_ioctl_supp_recv(struct tee_context *ctx,
 502                                struct tee_ioctl_buf_data __user *ubuf)
 503 {
 504         int rc;
 505         struct tee_ioctl_buf_data buf;
 506         struct tee_iocl_supp_recv_arg __user *uarg;
 507         struct tee_param *params;
 508         u32 num_params;
 509         u32 func;
 510
 511         if (!ctx->teedev->desc->ops->supp_recv)
 512                 return -EINVAL;
 513
 514         if (copy_from_user(&buf, ubuf, sizeof(buf)))
 515                 return -EFAULT;
 516
 517         if (buf.buf_len > TEE_MAX_ARG_SIZE ||
 518             buf.buf_len < sizeof(struct tee_iocl_supp_recv_arg))
 519                 return -EINVAL;
 520
 521         uarg = u64_to_user_ptr(buf.buf_ptr);
 522         if (get_user(num_params, &uarg->num_params))
 523                 return -EFAULT;
 524
 525         if (sizeof(*uarg) + TEE_IOCTL_PARAM_SIZE(num_params) != buf.buf_len)
 526                 return -EINVAL;
 527
 528         params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
 529         if (!params)
 530                 return -ENOMEM;
 531
 532         rc = params_from_user(ctx, params, num_params, uarg->params);
 533         if (rc)
 534                 goto out;
 535
 536         rc = ctx->teedev->desc->ops->supp_recv(ctx, &func, &num_params, params);
 537         if (rc)
 538                 goto out;
 539
 540         if (put_user(func, &uarg->func) ||
 541             put_user(num_params, &uarg->num_params)) {
 542                 rc = -EFAULT;
 543                 goto out;
 544         }
 545
 546         rc = params_to_supp(ctx, uarg->params, num_params, params);
 547 out:
 548         kfree(params);
 549         return rc;
 550 }
 551
 552 static int params_from_supp(struct tee_param *params, size_t num_params,
 553                             struct tee_ioctl_param __user *uparams)
 554 {
 555         size_t n;
 556
 557         for (n = 0; n < num_params; n++) {
 558                 struct tee_param *p = params + n;
 559                 struct tee_ioctl_param ip;
 560
 561                 if (copy_from_user(&ip, uparams + n, sizeof(ip)))
 562                         return -EFAULT;
 563
 564                 /* All unused attribute bits has to be zero */
 565                 if (ip.attr & ~TEE_IOCTL_PARAM_ATTR_MASK)
 566                         return -EINVAL;
 567
 568                 p->attr = ip.attr;
 569                 switch (ip.attr & TEE_IOCTL_PARAM_ATTR_TYPE_MASK) {
 570                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
 571                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
 572                         /* Only out and in/out values can be updated */
 573                         p->u.value.a = ip.a;
 574                         p->u.value.b = ip.b;
 575                         p->u.value.c = ip.c;
 576                         break;
 577                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
 578                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
 579                         /*
 580                          * Only the size of the memref can be updated.
 581                          * Since we don't have access to the original
 582                          * parameters here, only store the supplied size.
 583                          * The driver will copy the updated size into the
 584                          * original parameters.
 585                          */
 586                         p->u.memref.shm = NULL;
 587                         p->u.memref.shm_offs = 0;
 588                         p->u.memref.size = ip.b;
 589                         break;
 590                 default:
 591                         memset(&p->u, 0, sizeof(p->u));
 592                         break;
 593                 }
 594         }
 595         return 0;
 596 }
 597
 598 static int tee_ioctl_supp_send(struct tee_context *ctx,
 599                                struct tee_ioctl_buf_data __user *ubuf)
 600 {
 601         long rc;
 602         struct tee_ioctl_buf_data buf;
 603         struct tee_iocl_supp_send_arg __user *uarg;
 604         struct tee_param *params;
 605         u32 num_params;
 606         u32 ret;
 607
 608         /* Not valid for this driver */
 609         if (!ctx->teedev->desc->ops->supp_send)
 610                 return -EINVAL;
 611
 612         if (copy_from_user(&buf, ubuf, sizeof(buf)))
 613                 return -EFAULT;
 614
 615         if (buf.buf_len > TEE_MAX_ARG_SIZE ||
 616             buf.buf_len < sizeof(struct tee_iocl_supp_send_arg))
 617                 return -EINVAL;
 618
 619         uarg = u64_to_user_ptr(buf.buf_ptr);
 620         if (get_user(ret, &uarg->ret) ||
 621             get_user(num_params, &uarg->num_params))
 622                 return -EFAULT;
 623
 624         if (sizeof(*uarg) + TEE_IOCTL_PARAM_SIZE(num_params) > buf.buf_len)
 625                 return -EINVAL;
 626
 627         params = kcalloc(num_params, sizeof(struct tee_param), GFP_KERNEL);
 628         if (!params)
 629                 return -ENOMEM;
 630
 631         rc = params_from_supp(params, num_params, uarg->params);
 632         if (rc)
 633                 goto out;
 634
 635         rc = ctx->teedev->desc->ops->supp_send(ctx, ret, num_params, params);
 636 out:
 637         kfree(params);
 638         return rc;
 639 }
 640
 641 static long tee_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 642 {
 643         struct tee_context *ctx = filp->private_data;
 644         void __user *uarg = (void __user *)arg;
 645
 646         switch (cmd) {
 647         case TEE_IOC_VERSION:
 648                 return tee_ioctl_version(ctx, uarg);
 649         case TEE_IOC_SHM_ALLOC:
 650                 return tee_ioctl_shm_alloc(ctx, uarg);
 651         case TEE_IOC_SHM_REGISTER:
 652                 return tee_ioctl_shm_register(ctx, uarg);
 653         case TEE_IOC_OPEN_SESSION:
 654                 return tee_ioctl_open_session(ctx, uarg);
 655         case TEE_IOC_INVOKE:
 656                 return tee_ioctl_invoke(ctx, uarg);
 657         case TEE_IOC_CANCEL:
 658                 return tee_ioctl_cancel(ctx, uarg);
 659         case TEE_IOC_CLOSE_SESSION:
 660                 return tee_ioctl_close_session(ctx, uarg);
 661         case TEE_IOC_SUPPL_RECV:
 662                 return tee_ioctl_supp_recv(ctx, uarg);
 663         case TEE_IOC_SUPPL_SEND:
 664                 return tee_ioctl_supp_send(ctx, uarg);
 665         default:
 666                 return -EINVAL;
 667         }
 668 }
 669
 670 static const struct file_operations tee_fops = {
 671         .owner = THIS_MODULE,
 672         .open = tee_open,
 673         .release = tee_release,
 674         .unlocked_ioctl = tee_ioctl,
 675         .compat_ioctl = tee_ioctl,
 676 };
 677
 678 static void tee_release_device(struct device *dev)
 679 {
 680         struct tee_device *teedev = container_of(dev, struct tee_device, dev);
 681
 682         spin_lock(&driver_lock);
 683         clear_bit(teedev->id, dev_mask);
 684         spin_unlock(&driver_lock);
 685         mutex_destroy(&teedev->mutex);
 686         idr_destroy(&teedev->idr);
 687         kfree(teedev);
 688 }
 689
 690 /**
 691  * tee_device_alloc() - Allocate a new struct tee_device instance
 692  * @teedesc:    Descriptor for this driver
 693  * @dev:        Parent device for this device
 694  * @pool:       Shared memory pool, NULL if not used
 695  * @driver_data: Private driver data for this device
 696  *
 697  * Allocates a new struct tee_device instance. The device is
 698  * removed by tee_device_unregister().
 699  *
 700  * @returns a pointer to a 'struct tee_device' or an ERR_PTR on failure
 701  */
 702 struct tee_device *tee_device_alloc(const struct tee_desc *teedesc,
 703                                     struct device *dev,
 704                                     struct tee_shm_pool *pool,
 705                                     void *driver_data)
 706 {
 707         struct tee_device *teedev;
 708         void *ret;
 709         int rc, max_id;
 710         int offs = 0;
 711
 712         if (!teedesc || !teedesc->name || !teedesc->ops ||
 713             !teedesc->ops->get_version || !teedesc->ops->open ||
 714             !teedesc->ops->release || !pool)
 715                 return ERR_PTR(-EINVAL);
 716
 717         teedev = kzalloc(sizeof(*teedev), GFP_KERNEL);
 718         if (!teedev) {
 719                 ret = ERR_PTR(-ENOMEM);
 720                 goto err;
 721         }
 722
 723         max_id = TEE_NUM_DEVICES / 2;
 724
 725         if (teedesc->flags & TEE_DESC_PRIVILEGED) {
 726                 offs = TEE_NUM_DEVICES / 2;
 727                 max_id = TEE_NUM_DEVICES;
 728         }
 729
 730         spin_lock(&driver_lock);
 731         teedev->id = find_next_zero_bit(dev_mask, max_id, offs);
 732         if (teedev->id < max_id)
 733                 set_bit(teedev->id, dev_mask);
 734         spin_unlock(&driver_lock);
 735
 736         if (teedev->id >= max_id) {
 737                 ret = ERR_PTR(-ENOMEM);
 738                 goto err;
 739         }
 740
 741         snprintf(teedev->name, sizeof(teedev->name), "tee%s%d",
 742                  teedesc->flags & TEE_DESC_PRIVILEGED ? "priv" : "",
 743                  teedev->id - offs);
 744
 745         teedev->dev.class = tee_class;
 746         teedev->dev.release = tee_release_device;
 747         teedev->dev.parent = dev;
 748
 749         teedev->dev.devt = MKDEV(MAJOR(tee_devt), teedev->id);
 750
 751         rc = dev_set_name(&teedev->dev, "%s", teedev->name);
 752         if (rc) {
 753                 ret = ERR_PTR(rc);
 754                 goto err_devt;
 755         }
 756
 757         cdev_init(&teedev->cdev, &tee_fops);
 758         teedev->cdev.owner = teedesc->owner;
 759         teedev->cdev.kobj.parent = &teedev->dev.kobj;
 760
 761         dev_set_drvdata(&teedev->dev, driver_data);
 762         device_initialize(&teedev->dev);
 763
 764         /* 1 as tee_device_unregister() does one final tee_device_put() */
 765         teedev->num_users = 1;
 766         init_completion(&teedev->c_no_users);
 767         mutex_init(&teedev->mutex);
 768         idr_init(&teedev->idr);
 769
 770         teedev->desc = teedesc;
 771         teedev->pool = pool;
 772
 773         return teedev;
 774 err_devt:
 775         unregister_chrdev_region(teedev->dev.devt, 1);
 776 err:
 777         pr_err("could not register %s driver\n",
 778                teedesc->flags & TEE_DESC_PRIVILEGED ? "privileged" : "client");
 779         if (teedev && teedev->id < TEE_NUM_DEVICES) {
 780                 spin_lock(&driver_lock);
 781                 clear_bit(teedev->id, dev_mask);
 782                 spin_unlock(&driver_lock);
 783         }
 784         kfree(teedev);
 785         return ret;
 786 }
 787 EXPORT_SYMBOL_GPL(tee_device_alloc);
 788
 789 static ssize_t implementation_id_show(struct device *dev,
 790                                       struct device_attribute *attr, char *buf)
 791 {
 792         struct tee_device *teedev = container_of(dev, struct tee_device, dev);
 793         struct tee_ioctl_version_data vers;
 794
 795         teedev->desc->ops->get_version(teedev, &vers);
 796         return scnprintf(buf, PAGE_SIZE, "%d\n", vers.impl_id);
 797 }
 798 static DEVICE_ATTR_RO(implementation_id);
 799
 800 static struct attribute *tee_dev_attrs[] = {
 801         &dev_attr_implementation_id.attr,
 802         NULL
 803 };
 804
 805 static const struct attribute_group tee_dev_group = {
 806         .attrs = tee_dev_attrs,
 807 };
 808
 809 /**
 810  * tee_device_register() - Registers a TEE device
 811  * @teedev:     Device to register
 812  *
 813  * tee_device_unregister() need to be called to remove the @teedev if
 814  * this function fails.
 815  *
 816  * @returns < 0 on failure
 817  */
 818 int tee_device_register(struct tee_device *teedev)
 819 {
 820         int rc;
 821
 822         if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED) {
 823                 dev_err(&teedev->dev, "attempt to register twice\n");
 824                 return -EINVAL;
 825         }
 826
 827         rc = cdev_add(&teedev->cdev, teedev->dev.devt, 1);
 828         if (rc) {
 829                 dev_err(&teedev->dev,
 830                         "unable to cdev_add() %s, major %d, minor %d, err=%d\n",
 831                         teedev->name, MAJOR(teedev->dev.devt),
 832                         MINOR(teedev->dev.devt), rc);
 833                 return rc;
 834         }
 835
 836         rc = device_add(&teedev->dev);
 837         if (rc) {
 838                 dev_err(&teedev->dev,
 839                         "unable to device_add() %s, major %d, minor %d, err=%d\n",
 840                         teedev->name, MAJOR(teedev->dev.devt),
 841                         MINOR(teedev->dev.devt), rc);
 842                 goto err_device_add;
 843         }
 844
 845         rc = sysfs_create_group(&teedev->dev.kobj, &tee_dev_group);
 846         if (rc) {
 847                 dev_err(&teedev->dev,
 848                         "failed to create sysfs attributes, err=%d\n", rc);
 849                 goto err_sysfs_create_group;
 850         }
 851
 852         teedev->flags |= TEE_DEVICE_FLAG_REGISTERED;
 853         return 0;
 854
 855 err_sysfs_create_group:
 856         device_del(&teedev->dev);
 857 err_device_add:
 858         cdev_del(&teedev->cdev);
 859         return rc;
 860 }
 861 EXPORT_SYMBOL_GPL(tee_device_register);
 862
 863 void tee_device_put(struct tee_device *teedev)
 864 {
 865         mutex_lock(&teedev->mutex);
 866         /* Shouldn't put in this state */
 867         if (!WARN_ON(!teedev->desc)) {
 868                 teedev->num_users--;
 869                 if (!teedev->num_users) {
 870                         teedev->desc = NULL;
 871                         complete(&teedev->c_no_users);
 872                 }
 873         }
 874         mutex_unlock(&teedev->mutex);
 875 }
 876
 877 bool tee_device_get(struct tee_device *teedev)
 878 {
 879         mutex_lock(&teedev->mutex);
 880         if (!teedev->desc) {
 881                 mutex_unlock(&teedev->mutex);
 882                 return false;
 883         }
 884         teedev->num_users++;
 885         mutex_unlock(&teedev->mutex);
 886         return true;
 887 }
 888
 889 /**
 890  * tee_device_unregister() - Removes a TEE device
 891  * @teedev:     Device to unregister
 892  *
 893  * This function should be called to remove the @teedev even if
 894  * tee_device_register() hasn't been called yet. Does nothing if
 895  * @teedev is NULL.
 896  */
 897 void tee_device_unregister(struct tee_device *teedev)
 898 {
 899         if (!teedev)
 900                 return;
 901
 902         if (teedev->flags & TEE_DEVICE_FLAG_REGISTERED) {
 903                 sysfs_remove_group(&teedev->dev.kobj, &tee_dev_group);
 904                 cdev_del(&teedev->cdev);
 905                 device_del(&teedev->dev);
 906         }
 907
 908         tee_device_put(teedev);
 909         wait_for_completion(&teedev->c_no_users);
 910
 911         /*
 912          * No need to take a mutex any longer now since teedev->desc was
 913          * set to NULL before teedev->c_no_users was completed.
 914          */
 915
 916         teedev->pool = NULL;
 917
 918         put_device(&teedev->dev);
 919 }
 920 EXPORT_SYMBOL_GPL(tee_device_unregister);
 921
 922 /**
 923  * tee_get_drvdata() - Return driver_data pointer
 924  * @teedev:     Device containing the driver_data pointer
 925  * @returns the driver_data pointer supplied to tee_register().
 926  */
 927 void *tee_get_drvdata(struct tee_device *teedev)
 928 {
 929         return dev_get_drvdata(&teedev->dev);
 930 }
 931 EXPORT_SYMBOL_GPL(tee_get_drvdata);
 932
 933 static int __init tee_init(void)
 934 {
 935         int rc;
 936
 937         tee_class = class_create(THIS_MODULE, "tee");
 938         if (IS_ERR(tee_class)) {
 939                 pr_err("couldn't create class\n");
 940                 return PTR_ERR(tee_class);
 941         }
 942
 943         rc = alloc_chrdev_region(&tee_devt, 0, TEE_NUM_DEVICES, "tee");
 944         if (rc) {
 945                 pr_err("failed to allocate char dev region\n");
 946                 class_destroy(tee_class);
 947                 tee_class = NULL;
 948         }
 949
 950         return rc;
 951 }
 952
 953 static void __exit tee_exit(void)
 954 {
 955         class_destroy(tee_class);
 956         tee_class = NULL;
 957         unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);
 958 }
 959
 960 subsys_initcall(tee_init);
 961 module_exit(tee_exit);
 962
 963 MODULE_AUTHOR("Linaro");
 964 MODULE_DESCRIPTION("TEE Driver");
 965 MODULE_VERSION("1.0");
 966 MODULE_LICENSE("GPL v2");